Strona. — Development of Color in Feathers. 
PLATE 2. 
All Figures nragnified 495 diameters. 
Fig. 10. Transverse section of barb from blue feather of Cotinga cayana. 
Fig. 11. Transverse section of barb from blue wing-feather of Pitta moluccensis. 
Figures 12-14 are portions of transverse sections of wing-feathers from Sterna 
hirundo. 
Fig. 12. Section at level of 12 in Fig. 1. The position of the part of the section 
here shown is indicated in Figure 2 by the asterisk (*). crs’. Small 
ridge in epithelium preceding formation of barb ridges. 
Fig. 18. Section at the level 13, in Figure 1. c/’. Dividing cell. 
Fig. 14. Section at the level 14 in Figure 1. 
